http://arxiv.org/abs/2304.08827
We present a possible evolutionary pathway to form planetary nebulae (PNe) with close neutron star (NS)-white dwarf (WD) binary central stars. By employing a comprehensive binary population synthesis technique we find that the evolution involves two common envelope evolution (CEE) phases and a core collapse supernova explosion between them that forms the NS. Later the lower mass star engulfs the NS as it becomes a red giant, a process that leads to the second CEE phase and to the ejection of the envelope. This leaves a hot horizontal branch star that evolves to become a helium WD and an expanding nebula. Both the WD and the NS power the nebula. The NS in addition might power a pulsar wind nebula inside the expanding PN. From our simulations we find that the Galactic formation rate of NS-WD PNe is $1.8 \times 10^{-5} {\rm yr}^{-1}$ while the Galactic formation rate of all PNe is $0.42 {\rm yr}^{-1}$. There is a possibility that one of the observed Galactic PNe might be a NS-WD PN, and a few NS-WD PNe might exist in the Galaxy. The central binary systems might be sources for future gravitational wave detectors like LISA, and possibly of electromagnetic telescopes.
I. Ablimit and N. Soker
Wed, 19 Apr 23
41/58
Comments: 8 pages, 4 figures, one appendix with 3 tables; Will be submitted to MNRAS, comments welcome